The Love of God Comes via Faith - Ephesians 3:16-19

That he would grant you, according to the riches of his glory, to be strengthened with might by his Spirit in the inner man;
That Christ may dwell in your hearts by faith; that ye, being rooted and grounded in love, may be able to comprehend with all saints what is the breadth, and length, and depth, and height;
And to know the love of Christ, which passeth knowledge, that ye might be filled with all the fulness of God.

The light of Christ brings us pure knowledge. (Remember - the glory of God is intelligence, in other words, light and truth.) The medium by which the knowledge is passed to us is the Spirit (Holy Ghost), and it is done by faith. Through which reception the love of God (charity, which is the pure love of Christ) can be ours.

It seems that exercising faith in Christ, in other words, following the urgings of the spirit, which urgings originate in the light of Christ, will lead us to the love of God. The most joyous to the soul!

This part about Christ dwelling in our hearts merits further investigation.
In John 14:23 we read:

Jesus said unto him, if a man love me, he will keep my words: and my father will love him and we will come unto him and make our abode with him.

Doctrine and Covenants 130:3:

[In] John 14:23 - The appearing of the Father and the Son, in that verse, is a personal appearance; and the idea that the Father and the Son dwell in a man’s heart is an old sectarian notion, and is false.

So we are instructed that the Father and the Son do not physically dwell inside of us. But there are still some statements that are confusing in this regard. Like this one:

Alma 34:36:

...He dwelleth not in unholy temples, but in the hearts of the righteous doth He dwell...

However, this scripture enforces the point of the impossibility of Him to dwell inside of us:

2 Nephi 2:8:

...there is no flesh that can dwell in the presence of God, save it be through the merits, and mercy,and grace of the Holy Messiah...

This scripture also further clarifies the statement in John 14:23, because Christ is telling the disciples that it is the Comforter who will be sent to them:

John 14:26:

The comforter, which is the Holy Ghost, whom the father will send in my name, he shall teach you all things, and bring all things to your remembrance...

Finally, in the great intercessory prayer, Christ's words help us understand what it means to be one with Him; Luke 17:20-26:

Neither pray I for these alone (meaning the disciples), but for them also which shall believe on me through their word;
That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.

Notice that He asks that the disciples and all who should believe on Him would be "one as thou, Father art in me, and I in thee". So He's asking that the disciples be made one with the Father in the same way that Christ is one with the Father. And lest we should think that should mean to be physically morphed into one, we must read on, because He clarifies, how it is done...

And the glory which thou gavest me I have given them; that they may be one, even as we are one: I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me.
Father, I will that they also, whom thou hast given me, be with me where I am; that they may behold my glory,which thou hast given me...

 He says that He has given them of the glory that He received from the Father that they be made perfect and that they may be with Him where He is.

So it would appear that to be "one" with both the Father and the Son, is to be glorified and made perfected so that we may be with Him in the same way He is with the father. But wait a second - This was before the crucifixion, Peter would still deny Him, and all of them would be discouraged at His death. Does it sound like these men were perfected at that time?

Well, the answer is the Spirit - It performs many functions besides being a comforter and bringing things to our remembrance as we read in John 14:26. It also cleanses and purifies us, and is the medium through which we receive all truth through the light of Christ. To have the spirit with you is to be clean, to be glorified, and to be perfected. Now I have yet to meet the person who is so in tune as to have the Spirit with them 24/7, but the point is that it is possible. And this is the exact gift that Christ was praying for in the intercessory prayer - that His disciples have access to His glory and truth through the Spirit to make them "one".

So when we read about Him dwelling in our hearts, or being inside us - just remember that it is meant that He is with us vicariously through the Spirit.